If you want to attract butterflies to your garden, you need to provide plants that will give them places to transform and to eat.

That’s a simple formula, but not one that many gardeners consider. Susan Dunlap, founder and CEO of FindPlants.net, and an expert in plant identification and selection, has dedicated the past several years of her life to studying the nation’s butterflies and their needs.

Here are some of her tips on growing a butterfly garden.

The butterfly’s palate is not as narrow as we once thought. There are 608 nectar feeding species of butterflies and more than 37,000 plants that can support them, although not all butterflies live on all of them.

The common belief that butterflies need a wide landing platform to feed from doesn’t hold up in most cases. Dunlap says most butterflies have the ability to grasp even fine parts of a plant.

If you want to know what plants would be good for attracting a variety of butterflies, check the plant lists at regional parks. Dunlap believes one of the reasons Contra Costa County has 101 known species of butterflies is partly because of the warmer temperatures, and partly because of the abundance of regional parks and the plants they grow. San Mateo County, which is cooler and doesn’t have as many regional parks, has about 80 species of butterflies.

Before selecting plants, study your area to see what species of butterflies live there, then pick the plants that are known to support those butterflies.

Not all butterfly friendly plants are cultivated. Some butterflies like weeds, including dandelions.

For more information on butterflies and what plants they like, go to Dunlap’s website.

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